摘要
Influence of A1 content on the machinability of AZ series cast Mg alloys was investigated. In order to evaluate the machinability of the alloys, measurements of the cutting forces during turning operations and surface roughness were carried out as well as considering the microstructure and tensile properties. The results show that maximum tensile properties are observed with 2% （mass fraction） A1 addition to Mg. As the A1 content of the alloy increases above 2%, the cutting forces tend to reduce along with the ductility owing to the grain boundary precipitation of intermetallic phase （fl-Mgl7All2）. Cutting forces are able to increase as the cutting speed increases for all the alloys studied, and it＇s attributed to flank built up at the tip of the cutting tool during machining.
研究铝含量对AZ系列铸造铝合金机械加工性能的影响。为评价该合金的机械加工性能,测量切削操作过程中的切削力以及表面粗糙度,以及研究显微组织和拉伸性能。结果表明:添加2%铝含量的镁合金具有最佳的拉伸性能。随着铝含量增加到2%以上,由于晶界上析出金属间化合物β-Mg17Al12,切削力会随延展性的降低而降低。切削力也会随着切削速度的增加而增大,这是由于在加工过程中切削工具的尖端有侧面生成。
